Doctors are set to operate on a toddler from China who appears to have a foetus in her belly.

It is believed that the tiny baby inside Kang Mengru is her parasitic twin.

Medics discovered the foetus in a CT scan, carried out following confusion over Kang's enlarged belly.

The toddler was reportedly left by her biological parents at the age of one, and has since been adopted.

A doctor is quoted as saying, "She would be die unless she has the surgery immediately."

However, it is understood that the family needs financial help in order to pay for the operation.

It is extremely rare for a foetus to be trapped inside another, but it can apparently survive using its twin's blood supply.